Field of the Disclosure
The present disclosure relates generally to wireless power transmission, and more specifically, to a transmitter apparatus which transmits wireless power at high power transmission efficiency to power or charge electronic devices.
Background Information
A plurality of electronic devices are powered via rechargeable batteries. Such devices include smartphones, portable gaming devices, tablet computers, portable music players, laptop computers, computer peripheral devices, communication devices (e.g., Bluetooth devices), digital cameras, and hearing aids, amongst others. While battery technology has improved, battery-powered electronic devices increasingly require and consume greater amounts of power, thereby often requiring recharging. Rechargeable devices are often charged via wired connections through cables or other similar connectors that are physically connected to a power supply.
Wireless charging technology has been developed and used for electronic devices in an effort to solve problems presented by wired charging solutions, such as contamination of contact terminals and moisture preventing the appropriate charging of the battery in the electronic device. Wireless charging systems may be capable of transferring power in free space and provide power to electronic devices or can be used to charge rechargeable electronic devices. Wireless power transmission is performed through a transmitter and a receiver coupled to the electronic device to be charged. The receive antenna collects power from the transmitter and rectifies it for charging the battery.
Wireless power transmission (WPT) using radio frequency (RF) waves has been enabled in a plurality of applications, such as power transmission from space to earth and microwave-powered aircraft; powering of devices using an inductive resonance coupling scheme that makes use of near-field coupling between two magnetic resonators; and development of antenna arrays to harvest very low power levels from an RF transmitter located within a very short distance; amongst other applications.
During WPT using RF waves, power losses occur due to factors, such as RF-to-direct-current (RF-DC) conversion, hardware configuration and control logic for transmission, and RF propagation, amongst others. Recent developments have reduced losses from RF-DC conversion and spatial beam-forming improving the RF propagation efficiency.
Notwithstanding developments in current art, there is still a gap between existing technologies and practical WPT. Specifically, reliability in charging portable devices in complex environments of everyday life, efficient wireless power transmission, safety assurance, and cost, size and weight reduction of components for a wireless power transmission system.
As such, there is a need for a wireless power transmitter which addresses the previously mentioned limitations and more particularly, capable of transmitting wireless power with hardware components of lower cost and compactness which can provide high power efficiency.